Guns Across Red River by A A Glynn

Dannehar just stopped in town to get something to eat.  Instead, he gets a gun in his back and the sheriff tells him he'll be spending his night in jail.  Anyone who comes to town with a gun gets that treatment.  Dannehar knows Oskin.  They've both been soldiers and then lawmen after the war.  He goes along with it and gets a good meal out of it.  Then he and the boy he's jailed with work an old trick and he escapes.  That was working great until he gets pinned down by the river by a couple of men in the rocks above him.  They have rifles.  He just has his pistol.  The odds aren't good.

Pioneering Press allowed me to read this ebook for review (thank you).  It has been published and you can get a copy now.

He's lucky, Oskin has a rifle and takes them out and then joins him.  He's surprised to see him but Oskin was getting antsy about his job as sheriff and the adventuring bug hit him when Dannehar came through.  Dannehar explains he's going to help a negro who saved his life during the war.  He was drowning and he got him out of the river.  They shook hands and then went back to the war:  one on one side and one on the other.  This man needs help because someone is trying to run the Indians and the others in the town out.  

What they find is ugly.  There are bad men on the way to that location, too, and there are gunfights on the way.  When they see a burned out ranch, they run into a good batch of men bracing them.  They think it's over, but there's a black man in the midst of them and he vouches for them.  It seems there's oil in the ground on the Indian side of the river and the driller is determined to get it.  They won't sell, so he'll take it by force.

The action gets hot and the bullets fly but the boys have lots of experience dodging them.  Once the war is over, Dannehar is off to look up a widow he knew in earlier days.  Oskin comes along.  Dannehar's going to get teased all the way there...

This is a very good western.  Give it a try.